Retractable room actuation assembly for recreational vehicle

ABSTRACT

A slide-out or retractable room for a mobile living quarters, such as a recreational vehicle, is provided with actuating assemblies mounted on opposite side walls of the slide-out room and the adjacent wall of the main living area. The actuating assemblies include a pair of parallel gear racks mounted on the side wall, which are engaged by pinions rotated by torque shafts mounted on the main living quarters. Each torque shaft is rotated by a separate motor. A roller engages a bearing surface on the lower portion of the gear racks. Accordingly, the slide-out room is extended and retracted by rotating the torque shafts to cause the gear racks and the attached slide-out room to extend and retract. The weight of the slide-out room is supported by the rollers, thereby supporting the slide-out room off of the floor of the main living quarters as it extends and retracts. A synchronizing control operates the motors.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims domestic priority based upon U.S. ProvisionalPatent Application Ser. No. 61/205,551, filed Jan. 21, 2009, thedisclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

This invention relates to a slide-out or retractable room for mobileliving quarters, such as a recreation vehicle.

Recreational vehicles, such as motor homes, fifth-wheel trailers, andtravel trailers may be provided with a retractable or slide-out room forincreasing the living space of the vehicle. The retractable or slide-outroom is extended for use when the vehicle is parked and is retractedinto the main living area of the vehicle when the vehicle is to bemoved. Existing retractable or slide-out rooms can be time-consuming anddifficult to install. Frequently, the operating mechanisms consist ofmany separate components that must be individually installed, connectedand adjusted by highly-trained employees when the unit is assembled.After the vehicle is put into service, adjustments by the vehicle ownerare often necessary. Furthermore, existing slide-out rooms requiresubstantial space for mounting large electrical motors and hydraulicunits that require the construction of expensive covers and thus reducethe overall space inside the vehicle. Such slide-out or retractablerooms are generally moved in and out of the vehicle across the floor ofthe main living area. Because the slide-out or retractable room isexposed to weather when extended, extension and retraction of theslide-out room causes staining and wear on the interior floor of thevehicle.

Generally, the physical size of the operating mechanism or slide-outroom is large and bulky and somehow has to be hidden. Concealing theoperating mechanism requires space either inside the vehicle, whichlessens the living space, or under the vehicle, which lessen room forthe mechanical systems such as storage tanks and axles. The object ofany slide-out room is to add space, so a need exists for a slidemechanism that requires no interior or exterior space.

Generally, existing mechanisms for extending and retracting slide-outrooms employ powerful hydraulic or electro-mechanical systems that havea fixed amount of working stroke. When actuated, these powerful deviceswill push or pull the slide room until they run out of useable stroke.When obstructions, such as trees on the exterior or furniture andsuitcases on the interior, are encountered before the wholly extended orwholly retracted position is attained, the actuation mechanism has morethen enough power to overcome the obstruction and keep going. This candestroy the slide-out room, which is generally made from light weightwood or aluminum tube. Sadly, sometimes human beings are encountered,often resulting in injury or death. Therefore, it is desirable thatobstructions be sensed and the actuation mechanism stopped,

Tolerances needed to construct slide-out rooms are large. Therefore, theside walls of the same slide-out room rarely have the same dimensions.When one side wall is deeper than the other side wall, only the shorterside wall can be adjusted to properly seal against the weather. Anexample is a slide-room that has one side wall built incrementallylonger than the other side wall. With a fixed stroke equal to the lengthof the shorter side wall, the longer side is unable to attain fullstroke and properly seal. This permits moisture to enter the unit andcause extensive damage. Therefore, a need exists for a slide roommechanism that can independently sense and automatically adjust stroketo a sealed position on each side of the slide room.

All known prior art for slide room mechanisms attach the actuatingmechanism to the unit. Sometimes the mechanism is mounted to the floorof the unit, or to the side wall, chassis or frame of the unit. Afterthe actuating mechanism is mounted on the unit, the slide-out room isattached. Due to natural manufacturing tolerances, the opening to acceptthe slide-out room typically varies from unit to unit in both height andwidth, while the slide-out room itself also varies in height and width.However, the seal used to keep weather out of the unit is manufacturedto a set dimension. Numerous adjustments up and down and left and rightare required to center the slide-out room to the opening in the unit inorder to provide a weather-tight seal when the room is extended andretracted. As the unit is used, normal road vibrations tend to cause theslide-out room to come out of adjustment, allowing moisture to enter theinterior of the vehicle causing extensive damage. Therefore, a needexists for a slide room mechanism that requires no mechanicaladjustment, both at installation and as it is used.

SUMMARY OF THE INVENTION

According to the present invention, actuating mechanisms are installedon opposite side walls of the slide-out room and the adjoining portionsof the wall of the main living area through which the slide-out roomextends and retracts. Each of the actuating assemblies include a pair ofpinion gears mounted on a rotatable torque shaft, which are supportedfor rotation on the main living quarters adjacent to the aperture in thewall of the main living quarters through which the slide-out roomextends and retracts. The two pinion gears rotate with a common shaft,and are meshed with the teeth of corresponding gear racks which aremounted on the adjacent side wall of the slide-out room. Rollers engagecorresponding bearing surfaces defined on the racks to support theslide-out room as it extends and retracts and also to assure that thepinions remain meshed with the racks. In an optional embodiment of theinvention, racks are provided with an inclined section, which permitsthe room to drop as it approaches the extended position to bring thefloor of the slide-out room flush with the floor of the main livingquarters, thereby eliminating the unsightly and inconvenient step-upbetween the slide-out room and the main living quarters.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view in perspective of the left hand actuating assembly ofthe slide-out room as it is shipped from the factory for installation onthe slide-out room; the right hand assembly being a mirror imagethereof;

FIG. 2 is a view in perspective of a portion of the actuating mechanismillustrated in FIG. 1, with the bearing blocks and cover eliminated toshow the internal torque shaft and pinions;

FIG. 3 is a view taken substantially along line 3-3 of FIG. 2;

FIG. 4 is an exploded view in perspective of a recreational vehicleincluding a slide-out room, with actuating assemblies of the presentinvention shown exploded off of the sides of the slide-out room;

FIG. 5 is a view in perspective of a slide-out room with actuatingassemblies made according to the present invention installed thereon;

FIG. 6 is a view similar to FIG. 5, but illustrating the manner in whichthe slide-out room slides into the main living quarters and the mannerin which the actuating assemblies are attached to the main livingquarters;

FIG. 7 is a view taken substantially along line 7-7 of FIG. 6;

FIG. 8 is a view taken substantially along line 8-8 of FIG. 7;

FIG. 9 is a view in perspective of a rack used in an alternateembodiment of the invention;

FIG. 10 is a schematic illustration of the control system used tocontrol system used to control the actuating assemblies used in thepresent invention; and

FIG. 11 is a detailed schematic of the control logic used in the controlsystem illustrated in FIG. 10.

DETAILED DESCRIPTION OF INVENTION

Referring now to the drawings, a mobile living quarters, such as arecreational vehicle, is indicated generally at 10, and includes a sidewall 12 (the remaining side walls of the vehicle 10 not being shown).Side wall 12 defines an aperture 14 through which a slide-out roomgenerally indicated by the number 16 extends and retracts. Slide-outroom 16 includes a front wall 18, two side walls 20, 22 extending fromthe front wall 18, a ceiling 24 and a floor 26.

An actuating mechanism comprises actuation assemblies 28, 30 that aremounted on the side walls 20, 22 respectively, the actuation assembly 30being a mirror image of the actuation assembly 28. As illustrated inFIGS. 1 and 4, each actuation assembly includes an upper rack orengagement member 32, a lower rack or engagement member 34, and a cover36 defining a column which covers the mechanism that drives the rack 32,34. Each of the racks or engagement members 32, 34 includes a pluralityof slots, as shown. Although rack and pinion actuators are shown, otherequivalent interengaging, relatively movable members, such as weldedchains and sprockets, a cog and stamping, timing belt and pulleys andother similar structures may be used; furthermore, although two rack andpinion assemblies are illustrated for each of the assemblies 28, 30, anynumber of assemblies may be used as necessary or convenient. Assemblystraps 38, 40 are illustrated in FIGS. 1 and 4; these assembly strapsare temporary to assure that the alignment of the racks 32, 34 remainparallel to each other. Assembly strap 38 includes a projecting flange42 that projects beyond the racks 32, 34 and is adapted to engage frontwall 18 of the slide-out room 16 to thereby locate actuating assembly 28laterally with respect to the slide-out room 16. As will hereinafter bedescribed, a bearing block covered by the cover of column 36 engages thefloor 26 of the slide-out room when the actuating assembly 28 isinstalled to thereby locate the actuating assembly vertically withrespect to the slide-out room 16. Accordingly, the actuating assemblies28, 30 are fully assembled when they are manufactured and shipped to theassembly plant for attachment to the slide-out room 16 and to the mainliving quarters. Accordingly, no separate components are required, andassemblies 28, 30 are inherently self-locating. Once the actuatingassemblies 28, 30 have been installed, the assembly straps 38, 40 areremoved and discarded.

The column or cover 36 includes a generally u-shaped portion 44 thatextends around the actuating components for the racks 32, 34, as willhereinafter be described. A flange 46 projects from the u-shaped portion44 and is provided with apertures 48, which receive fasteners 49 used toattach the actuating assemblies to the side wall 12 adjacent to theaperture 14. In addition to concealing and protecting the actuationcomponents, the column 36 trims up the edges of the aperture 14 and alsocarries a vertically extending bulb seal 50, which seals the unit whenthe retractable room is fully retracted into the main living area.

A drive member in the form of a splined torque shaft 52 extendssubstantially vertically in the cover of column 36 and is rotatablysupported by a lower bearing block 54 and an upper bearing block (notshown). The upper and lower bearing blocks have been omitted from FIG. 2for clarity and are substantially identical, so that only lower bearingblock 54 will be described in detail. Bearing block 54 has beenillustrated in phantom in FIGS. 3 and 7 for clarity. Torque shaft 52 isdefined by circumferentially spaced splines 56, which are received incorresponding grooves in pinions 58, 60, the pinions 58, 60 comprisingengagement features which mesh with the gear racks 32, 34, respectively.Upper and lower gear racks 32, 34 are substantially identical, exceptthat the lower gear rack 34 includes a flange 62 which projectstherefrom and engages the lower side of the floor 26 of the slide-outroom 16 to thereby locate the actuation assembly 28 vertically withrespect thereto.

A roller 64, having a substantially v-shaped cross section to definebearing faces 66, 68, is rotatably mounted on a spindle 70 projectingfrom bearing block 54. Rollers of other complex shapes may be usedinstead of v-shaped rollers illustrated, it only being necessary thatthe rollers be shaped to control the relative positions of the rack andthe roller, and to permit the slide-out room to move relative to theunit. The racks 32, 34 are each provided with a horizontally extendingbearing surface defined by angled bearing faces 72, 74. The bearingfaces will, of course, be shaped complementary to the cross section ofthe roller. A hooked extension extends from the bearing block 54 into alongitudinally extending groove 78 (FIG. 2) of the rack 34. Hookedextension 76 is covered by a low friction, plastic (Delrin) shoe 80which rides in the groove 78 as the slide-out room extends and retracts.The shoe 80 and groove 78 maintain engagement of the roller 64 with therack 34 and maintain engagement of the rack with the pinion bymaintaining a fixed predetermined distance therebetween. As describedabove, a bulb seal 50 extends along u-shaped portion 44 of the column36. As can be seen in FIG. 8, when the slide-out room 16 is in the fullyretracted position, an extension 84 carried by the slide-out room 16engages bulb seal 50, compressing the latter, to assure a weather-tightseal protecting the pinions, torque shafts, and motor from theenvironment.

An electric motor 82 is supported on the upper most end of the torqueshaft 52 for rotating the latter. The motor 82 is a bi-directionalmotor, and rotates the shaft in one direction to extend the slide-outroom from the main living quarters, and in the opposite direction toretract the slide-out into the main living quarters. The actuationassembly 30 on the opposite side wall 22 is a mirror image of theactuation assembly 28. Another motor identical to the motor 83 operatesactuation assembly 30. Both motors are driven by a synchronizing drivecontrol 90, as illustrated in FIG. 10 and FIG. 11, so that both theactuating assemblies extend and retract at substantially the same rate,as will hereinafter be described. Alternatively, a transverse shaftextending over the slide-out room and connected to both torque shafts 52by a gear drive may be used with only one motor.

Referring now to FIG. 10, synchronizing drive control 90 includes aprocessor 92, which transmits data to, and receives data from, a memory94. Input bus 96 for processor 92 receives a voltage input from voltagesensor 98, current sensor inputs 100 and 102, which input signalsmeasuring current draw of the corresponding motor, and tachometers orspeed sensor inputs 104, 106, which are connected to speed sensors foreach of the motors and which generate pulse trains that are proportionalto the rotational speed of the motors. Other inputs include 108 and 110,which transmit a signal from a wall switch within the unit which isoperated when the user desires to extend or retract the slide-out room.The effect of the inputs 108 and 110 is to reverse the direction ofrotation of the motors, but operation of the system 90 is otherwise thesame if the slide-out room is either extended or retracted. Processor 92includes a pulse width modulator which generates pulse width modulatedvoltage signals which are transmitted to the motors through output bus112, as indicated at 114 and 116.

Referring now to FIG. 11, when the user operates the wall switch toeither extend or retract the slide-out room, processor 92 responds bystarting the control routine, as indicated at 118. Both motors areaccelerated to their maximum speed, as indicated at 120, it being notedthat the maximum speed of the motors may be different (due, for example,to differences in weight carried on different sides of the slide-outroom). A test is made, as indicated at 122, to determine if either motorhas reached the stall threshold. This is done by comparing the currentdraw of each motor, as sensed by sensor inputs 100 and 102. The currentdraw of the motors increases substantially when the motor stalls out atthe end of the stroke of the slide-out room (such as when it attains thefully extended or fully retracted position, or when the slide-out roomencounters an obstruction requiring greatly increased power). If bothmotors are operating below the stall threshold, a check is made todetermine if the motors are operating within a predetermined speed rangeof one another, as indicated at 124. If the motors are operating outsideof the speed range, the pulse width of the voltage signal to the fastermotor is altered to slow the faster motor to within the speed range, asindicated at 126.

If the test at 122 indicates that one of the motors has reached thestall threshold, the stalled motor is dynamically braked, as indicatedat 128 (by switching terminals of the motor together), and a stall timeris started. As indicated at 130, the current draw of the other motor isthen tested to determine its stall threshold has been reached. If thestall threshold of the second motor has been reached, the second motoris braked (as indicated at 132), the values of the counts from the motorspeed sensors stored in memory are reset to zero (as indicated at 134),and the routine is ended. If the test made at 130 indicates the secondmotor has not yet stalled out, a test is made at 136 to determine if thestall timer has timed out. If the stall timer has timed out, the othermotor is stopped (as indicated at 138), whereupon the routine is ended.By continuing to operate the motor not reaching the stall thresholdafter the first motor reaching the stall threshold has been stopped,both sides of the slide-out room are independently brought intoengagement with their corresponding bulb seals 50, thus assuring sealingcompletely around the slide-out room. The stall force timer assures thatone motor will not be operated longer than a predetermined time periodafter the other motor has stalled, so that if the stalling is caused byone side of the slide-out room striking an obstruction, the motoractuating the other side will not operate indefinitely, or if theclearances across the slide-out room are sufficiently different thatboth sides of the slide-out room cannot be sealed, the system will notbe operated indefinitely.

In operation, when the user desires to extend the slide-out room 16, themotors 82 are caused to turn in a direction turning the pinions 58, 60to cause the racks, due to their engagement therewith, to be drivenoutwardly with respect to the main living quarters, thereby carrying theslide-out room with the rack. Rollers 64, due to their engagement withthe rack 34, carry the weight of the slide-out room and maintain thefloor 26 of the slide-out room raised above the floor of the main livingquarters. Accordingly, damage to the floor of the main living quarters,common in the prior arts when slide-out rooms are extended or retracted,is avoided. Since, as described above, actuating assemblies 28, 30 areshipped as a unit to the manufacturing plant, assembly and adjustment ofseparate components is not necessary. The slide-out room 16 is retractedinto the main living quarters by causing the motor 82 to turn in thereverse direction, thereby moving the racks 32, 34 into the main livingquarters, carrying the slide-out room 16 with them.

As discussed above, prior art slide-out rooms require multipleadjustments to center the slide-out room in the opening in the unit inorder to provide a weather-tight seal when the room is extended andretracted, and require periodic adjustments to re-center the slide-outroom to compensate for normal road vibrations. In the present invention,the actuating assemblies 28, 30 are located vertically on theircorresponding side walls 20, 22 by engagement of the flange 62 with thefloor 26, and are located horizontally on their corresponding side walls20, 22 by the flange 42 of the assembly straps 38, 40. The clearancebetween the slide-out room and the side of the aperture 14 is set byattachment of flange 62 to the side wall 12. Since the bulb seal 50 isattached to the column 36 when the actuating assemblies 28, 30 aremanufactured and proper positioning of the actuating assemblies 28, 30on their corresponding side walls is assured, no adjustment of theslide-out room after installation on the unit is required or possible.

Slide-out rooms tend to tip downward relative to the unit when extended,and this tipping must be resisted, requiring heavier and more powerfulactuators than would otherwise be necessary. In the present invention,tipping forces are transmitted through upper rack 32 and pinion 60 toapply a twisting force to the torque shaft 52, which is resisted by thetorsional stiffness of the torque shaft 52. The twisting forces aretransmitted through the torque shaft 52 to the lower pinion 58 and thelower rack 34, to thereby apply a countervailing force to the lowerportion of the slide-out room, thereby tending to right the slide-outroom. Accordingly, the power required of the motor 82 remains relativelysmall compared to prior art actuating mechanisms.

Referring now to FIG. 9, a modified rack 86 is provided with an upwardlyinclining portion 88. The operation of the unit equipped with theinclined rack 86 is the same as in the preferred embodiment, except thatwhen the pinion travels along the inclined section 88 the slide-out roomis allowed to drop gradually, thereby bringing the floor of theslide-out room into registry with the floor of the main living quarters.The pinions are allowed axial movement along the torque shaft, therebypermitting the pinions to remain in driving engagement with the rackteeth after the inclined section 88 is reached. Instead of the hookedextension 76 and shoe 80, the unit using the inclined rack 86 isprovided with a secondary roller having a v-shaped cross section (notshown). This secondary roller is much smaller than the roller 64, andengages bearing surfaces 89 in the groove 91, which extendslongitudinally just above the tooth portion of the rack. The function ofthe secondary roller is the same as the hooked extension 76 and shoe 80.

This invention is not limited to the details above, but may be modifiedwithin the scope of the following claims.

1. An actuating mechanism for living quarters having a main living areaand a retractable room movable relative to the main living area betweena retracted position retracted within the main living area and anextended position extended from the main living area to provide anauxiliary living area, said retractable room movable through an aperturein a side-wall of said living quarters, and an actuating mechanism formoving said retractable room between the extended and retractedpositions, said actuating mechanism comprising: a first pair ofengagement members fixed relative to said retractable room and movingwith said retractable room, each said engagement member having aplurality of slots; a pair of drive members, each drive member havingengagement features for engaging a corresponding engagement member, saiddrive members being driven together to move said retractable roombetween its retracted and extended positions; said drive members andengagement members being maintained at a constant distance between eachother regardless of changes in spacing between said retractable room andsaid aperture, and said drive members being mounted for lateral movementwithin an elongate column on said sidewall at said aperture.
 2. Anactuating mechanism as claimed in claim 1, wherein said engagementactuating mechanism includes a roller held at a fixed predetermineddistance from one said drive member, said roller having rollingengagement with a complementary bearing surface carried on saidretractable room, said fixed predetermined distance between said rollerand said bearing surface on said retractable room preventing movement ofsaid drive members away from said engagement member.
 3. An actuatingmechanism as claimed in claim 1, wherein said engagement actuatingmechanism includes a pair of rollers each being held at a predetermineddistance from a corresponding drive member, each said roller in rollingengagement with a corresponding complementary bearing surface carried onsaid retractable room so that said roller is restrained from lateralmovement relative to said complementary bearing surface, said rollersrestraining lateral movement of said drive members away from theircorresponding engagement members.
 4. An actuating mechanism as claimedin claim 2, wherein said complementary bearing surfaces carried on saidretractable room are included on said engagement members.
 5. Anactuation mechanism as claimed in claim 4, including a means forensuring said engagement members are substantially parallel.
 6. Anactuation mechanism as claimed in claim 4, wherein said rollers supportthe weight of said retractable room.
 7. An actuation mechanism asclaimed in claim 1, wherein said drive members are gears rotatingtogether and fixed from rotation relative to each other on a commonshaft.
 8. An actuation mechanism as claimed in claim 7, wherein saidengagement members are racks having a plurality of slots forinterengaging teeth on said gears.
 9. An actuating mechanism as claimedin claim 8, wherein said engagement actuating mechanism includes anupper engagement member for ensuring said rollers remain in contact withsaid bearing surfaces.
 10. An actuating mechanism as claimed in claim 8,wherein said engagement actuating mechanism includes a pair of rollerseach being held at a predetermined distance from a corresponding gear,each said roller in rolling engagement with a correspondingcomplementary bearing surface carried on said retractable room so thatsaid roller is restrained from lateral movement relative to saidcomplementary bearing surface, said rollers restraining lateral movementof said drive members away from their corresponding engagement members.11. An actuating mechanism as claimed in claim 10, wherein saidcomplementary bearing surfaces carried on said retractable room areincluded on said racks.
 12. An actuation mechanism as claimed in claim11, wherein said rollers support the weight of said retractable room.13. An actuation mechanism as claimed in claim 12, wherein said gears,common shaft, and said rollers are laterally movable together andrestrained from longitudinal movement within said elongate column. 14.An actuation mechanism as claimed in claim 12, wherein said elongatecolumn includes a mounting flange for mounting to the sidewall of avehicle.
 15. An actuation mechanism as claimed in claim 7, wherein theweight of said room is supported on rollers.
 16. An actuation mechanismas claimed in claim 1, including a means for ensuring said engagementmembers are substantially parallel.
 17. An actuation mechanism asclaimed in claim 1, wherein said engagement members are racks, saiddrive members are gears rotating together and fixed from rotationrelative to each other on a common shaft, said gears being slidable onsaid shaft to maintain engagement with their corresponding racks saidgears follow the inclined section of said rack.